Grate structure



G. P. CRYSLER. GRATE sRucTuR.

, APPLICATION FILED APR. x2, 1919. 1,39,883. Patented Mar. 1, 1921.

3 SHEETS-SHEET l.

G.l P, CRYSLER.

GRATE STRUCTURE.

APPLlcATxoN HLED APR. 12, |919.y

Patenfd Mar. 1,1921.v

3 SHEETS-SHEET 2- 27E #6a ZO?" G; P. CRYSLER. @RATE STRUCTURE.

' APPLICATION FIL-ED APRn l2, 1915. 1,369,883. Patented Mar. 1,1921.

3 SHEETS-SHEET 3.

i UNITE STA x GEORGE 1. cnvsrnn, or "CHiCAGo, ILLInois.

GRATE STRUCTURE.'

To all fwtomz't may concern:

Be it known that l, Groen P. CRYSLER, a citizen of the United States, residing at Chi-V cago, in the county of .Cook and State of lilinois, have invented `certain new and useful Improvements in Grate Structures, of which the following isy a specific-ation.. The invention .relates Ito improvements 1ngrate structures and has especial referenceV to structures of this character foi'steamboiL` j ers, orthe like. i

To eect the highest economy in consumption of fuel, the grate area of the furnace must bear an efficiency ratio tol the several variable factors,I 'unknown in many instances, until afrter the installation ofthe plant, of which Ithe furnace is a part. In'

someinstallations 10 to 30 pounds of coal' per square foot of grate surface area must` be consumed per hour in order to realize the maximum 'capacity of the associated boiler,` while in other situations, where the periods of firing are of lessfrequentintervals, such for example, as in house heatingy boilers, the

fuel consumption per square foot of grate'y area per hour is frequently'aslow as Sto 4 pounds of coal.

In the eXigencies of firing operation the re must at times be reduced to meet other conditions, in which case, with unchanged grate area, lthe ratio of 'air supplied to yor passing through' the ,grate becomes out of proportion Ito other factors because of the reduced air resistance resulting from a thin# ner fuel hed imposed upon the gra-te surface.' ,A poor quality ofcoal requires more grate surface rthan coal of. greater :thermic value; the -intensity of the draft, also, has a modifying effect upon the size of the grate best adapted-to produce the moist efficient Y Vconditions of operation and other variants disturb the coperativeequilibrium that has been established for maximum service.

`The object of the present invention is toL provide means for conveniently and quickly` reducing the e'ective grate areas. Another object is to vary the size or area of the ldraft throat, between the V bridge wall and the boiler coincidentally with a changeA in grate area.

Other, further and morespecic objects of my invention will become readily apparv ent, to persons skilled inthe art, from a consideration of the following description when takenv in conjunction with the drawings, wherein Figure lis a longitudinal section, showing aboiler in elevation' and 4furnace Iwith my 'improvement incorporated'ltherein. Fig. 2 is'an enlarged, fragmentary section of lthe movable bridge-.wall which fis adapted to be moved toward the'ringfdoorfor y l atentedMa-r. 1, 1921-. y Application fiiedaprii 12,1919. lSerial 110.289,671. i

decreasing the effective' area of the'grajte and A gas throat. F 3 is a section F ig. 2.

taken onf-line 3-3 of Fig. 1 is a section Itaken 'approximately on` i line 414-4 of Fig. 2.

Fig. 5 is part ofthe metalv frame work of."

the bridge wall.

i In allthe views the same reference characters are employed to. indicate similar parts. In the physical embodiment,in the drawings of which IhaveV shownmy improved structure, A is a boiler;` B is the furnace; C:

is the smoke flue behind the furnace. 10 in-V dicates the grate bars ofthe gralte,;which are set, preferably, slightly inclined, from their outer ends, inwardly `and downwardly, as

shown in F ig; l. -11 is'the foundation for'.

the movable bridge Wall 12.

. In Fig. l, vthe movablev bridgeWall l2 is iii position which it occupies when .all of' the grate surface is in effect. The bridge;

wall 12 is adapted lto be moved forward. over the grate "by the lever 13, to the positiony shown indot-ted lines, in which position the,v

bridge V.wall covers that partof the, grate which is thus made inoperative, thereby re-V ducing 'the effective area of the' grate. The,

bridge wall is preferably'madef of an iron framework, a vfragmentof which shown in Fig.V 5, in .whichfthere is containedfa plurality of inverted channel bars 14, joined togetlier, as alt 14', by rivets Ithat' pass throughE the upturned flanges ofthe channel bars.V j In the particular embodiment there are two and one-half such' channel bars put together in ing across the front of `the bridge `wall thisinanner, as shown in Fig. 1. Extendfoundationstructure 11, is an angle iron 15,

. 'upon which the inner ends -of the grate barsV res-t and upon the upper lsurface yof which` -rides the channelbarzs'lt, `thereby preventing a draf-t of air from the ash pit 16 into the smoke i'lue- C under the movable bridge wall. Side plates v1'? are joined -to the upfturnedl flanges of the channel bars 14 by angle' braces 18. There is a plate 17 located at vided with a series of downwardly and forwardly tapering spaced apart teeth 20, se-

cured together by integral chaplets. or lugs 21. The end tooth 22, Vat each end, is provided with a depression in which the tapered end 23 of the plate 17, is inserted, sc that the outside surfacev of 'the lteeth 22 and the v outside surface of the plates`17 will be inthe .same longitudinal plane and substantially flush with the respective inner surfaces of the walls 24, of the boiler setting.

The casting V19 is provided near its top surface with a longitudinally extending, angular part 27, which `extends longitudinally of the casting 19, but transversely of the boilery setting, to receive a firefproof structure 28, made, preferably, of the same -mafterial of which fire-bricks yare composed,

and preferably, molded in, or to fit the frame, substantiallylas shown in Figs. 1 and 2.

' Located on each side of the movable structure are rods, or bars 29, and'30, respec- V to dotted line position, shown in Fig. 1, the

movable bridgewall structure is thereby moved to its eXtreme forward position shown by the dotted lines. Extending through the structure 19, parallel with the grate surface 10, is a shaft35 that passes through the bars 29 and 3Q, as'at 36, and finds bearings there! in. Near each ofthe bars 29 and 30, at this point', is a roller 37, mounted on the shaft and adapted to roll over the top of the grate surface, consisting ofthe grate bars 10. In the rear Vofthe angle iron 15, on the foundation-11 for the bridge wall, are a plurality of track bars 38'having their uppersurfaces in substantially the same horizontal plane as the upper surface of the angle bar 15, and upon which the shiftable bridge wall is longitudinally movable. v Y

The firing door 39and the ash door 40 are provided, as usual, in structures of this character.

When it is desired to reduce the effective surface of the grate in the furnace B it is only necessary to movethe bridge wall section 12 forwardly, bypulling out the lever f 13 intodotted line position, or to any intermediate point. As the bridge wall moves forwardly the throat 41, for the hot prod-v v upon which the front issupported.

my name.

ucts of combustion, is reduced in vertical dimensions and hasthe effect to maintain,

rpractically, substantially constant the velocity of the gases proportional, to the firing grate surface area other conditions remaining unchanged. As the structure 12 is moved back, on. account of the inclination of they path in-whi'ch it is moved the throat 41 is enlarged in dimension, as clearly shown by comparison' of the dotted outlinewith the full line structure, thereby increasing the throat area to accommodate the Yin-5 largest demands and then contract the area ofthe surface in the manner-*described to harmonize with other conditionsv of operation. Y f

When a bed of coal lis packed upon the front end of the structure 19, or on the teeth thereof, air will pass into the said bed of coal from the openings between the teeth therebelow and thereby increase the oxidizing effect of the fuel at the point of most intense combustion, or at the pointV where the products of combustion pass out of the furnace over the top of the bridge wall. The air that vpasses through the toothed structure 20- suficies to keep it sufficientlyintense heat cool to prevent melting by the developed in the furnace.

While I have herein showny a single embodiment of my invention, for the purpose of clear'disclosure, it willbe manifest, to persons skilledin the art, that considerable variation may-be made in the configuration and general disposition of the parts, within the s ,cope of the appended claim.

Having described my invention, what I claim is 1 1' 'f 'A device of the 'character described 'havtallic'frontl for the bridge wall comprising-'a' series of downwardlyr and forwardly -in-' clined spacedeapart teeth, substantiallyregistering in verticalplanes with said grate bars Yto provide air conducting spaces between said teeth and rollers-back of the teeth end ofj the bridge wall In testimony whereof 1 hereunto subscribe GEORGE i). oRYsLER. i 

